======================================
| [  655.524729][    C2] 1 lock held by ksoftirqd/2/29:
| [ 655.524924][ C2] #0: ffffc9000020fbc0 ((&n->timer)){+.-.}-{0:0}, at: call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
| [  655.525323][    C2]
| [  655.525323][    C2] stack backtrace:
[  655.525580][    C2] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  655.525583][    C2] Call Trace:
[  655.525584][    C2]  <TASK>
[ 655.525588][ C2] dump_stack_lvl (lib/dump_stack.c:123) 
[ 655.525596][ C2] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6848) 
[ 655.525606][ C2] __icmp_send (./include/net/net_namespace.h:404 ./include/linux/netdevice.h:2669 net/ipv4/icmp.c:616) 
[ 655.525617][ C2] ? arch_stack_walk (arch/x86/kernel/stacktrace.c:24) 
[ 655.525628][ C2] ? unwind_next_frame (arch/x86/kernel/unwind_orc.c:495) 
[ 655.525633][ C2] ? __pfx___icmp_send (net/ipv4/icmp.c:596) 
[ 655.525641][ C2] ? __pfx_unwind_next_frame (arch/x86/kernel/unwind_orc.c:469) 
[ 655.525651][ C2] ? rcu_read_lock_any_held (kernel/rcu/update.c:386 kernel/rcu/update.c:380) 
[ 655.525658][ C2] ? validate_chain (kernel/locking/lockdep.c:3799 kernel/locking/lockdep.c:3819 kernel/locking/lockdep.c:3874) 
[ 655.525672][ C2] ? __pfx_validate_chain (kernel/locking/lockdep.c:3862) 
[ 655.525676][ C2] ? hlock_class (./arch/x86/include/asm/bitops.h:227 ./arch/x86/include/asm/bitops.h:239 ./include/asm-generic/bitops/instrumented-non-atomic.h:142 kernel/locking/lockdep.c:230) 
[ 655.525679][ C2] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 655.525689][ C2] ? __lock_acquire (kernel/locking/lockdep.c:5228) 
[ 655.525698][ C2] ipv4_send_dest_unreach (net/ipv4/route.c:1241) 
[ 655.525704][ C2] ? neigh_invalidate (net/core/neighbour.c:1008) 
[ 655.525709][ C2] ? __pfx_ipv4_send_dest_unreach (net/ipv4/route.c:1215) 
[ 655.525722][ C2] ipv4_link_failure (./include/linux/skbuff.h:1152 ./include/net/route.h:88 net/ipv4/route.c:1250) 
[ 655.525727][ C2] arp_error_report (./include/net/dst.h:429 net/ipv4/arp.c:296) 
[ 655.525734][ C2] neigh_invalidate (net/core/neighbour.c:1008) 
[ 655.525743][ C2] neigh_timer_handler (net/core/neighbour.c:1109 (discriminator 2)) 
[ 655.525752][ C2] ? __pfx_neigh_timer_handler (net/core/neighbour.c:1032) 
[ 655.525755][ C2] call_timer_fn (kernel/time/timer.c:1789) 
[ 655.525759][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 655.525762][ C2] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1779) 
[ 655.525766][ C2] ? __pfx_call_timer_fn (kernel/time/timer.c:1766) 
[ 655.525768][ C2] ? mark_lock (kernel/locking/lockdep.c:4729 (discriminator 3)) 
[ 655.525786][ C2] __run_timers (kernel/time/timer.c:1841 kernel/time/timer.c:2414) 
[ 655.525789][ C2] ? __pfx_neigh_timer_handler (net/core/neighbour.c:1032) 
[ 655.525800][ C2] ? __pfx___run_timers (kernel/time/timer.c:2385) 
[ 655.525808][ C2] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:107 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 655.525814][ C2] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 655.525818][ C2] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 655.525821][ C2] ? run_timer_softirq (kernel/time/timer.c:2426 kernel/time/timer.c:2418 kernel/time/timer.c:2435 kernel/time/timer.c:2445) 
[ 655.525831][ C2] run_timer_softirq (kernel/time/timer.c:2427 kernel/time/timer.c:2418 kernel/time/timer.c:2435 kernel/time/timer.c:2445) 
[ 655.525836][ C2] handle_softirqs (kernel/softirq.c:561) 
[ 655.525844][ C2] ? __pfx_run_ksoftirqd (kernel/softirq.c:943) 
[ 655.525850][ C2] run_ksoftirqd (kernel/softirq.c:418 kernel/softirq.c:951 kernel/softirq.c:942) 
[ 655.525852][ C2] smpboot_thread_fn (kernel/smpboot.c:164 (discriminator 3)) 
[ 655.525859][ C2] ? __pfx_smpboot_thread_fn (kernel/smpboot.c:107) 
[ 655.525865][ C2] kthread (kernel/kthread.c:464) 
[ 655.525871][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 655.525880][ C2] ? __pfx_kthread (kernel/kthread.c:413) 
[ 655.525886][ C2] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 655.525890][ C2] ? __pfx_kthread (kernel/kthread.c:413) 


Finger prints:
lockdep_rcu_suspicious:__icmp_send:ipv4_send_dest_unreach:ipv4_link_failure:arp_error_report